package com.itheima.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.common.BaseContext;
import com.itheima.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebFilter(filterName ="loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {

    public  static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)throws IOException, ServletException{
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求:{}",request.getRequestURI());
        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/user/sendMsg",
                "/user/login"
        };

        //判断本次请求是否需要处理
        boolean check = check(urls,requestURI);

        //不需要处理直接放行
        if(check) {
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request, response);
            return;
        }

        //判断登陆状态，如果已登录则直接放行
        if(request.getSession().getAttribute("employee")!=null){
            log.info("用户已登录，用户id为；{}",request.getSession().getAttribute("employee"));
            //获取Id
            Long empId= (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            long id=Thread.currentThread().getId();
            log.info("线程id为:{}",id);
            filterChain.doFilter(request,response);
            return;
        }

        //4-2.判断登录状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user")!=null){
            log.info("用户已登录，用户id为；{}",request.getSession().getAttribute("user"));

            //获取Id
            Long userId= (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        log.info("用户未登录");
        //如果未登录则返回未登录结果,通过输出流的方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public  boolean check(String[] urls,String requestURI){
        for(String url:urls){
            boolean match = PATH_MATCHER.match(url,requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }

}
